Nuprl Lemma : union_functionality_wrt_uiff
∀[P1,P2,Q1,Q2:ℙ]. ({uiff(P1;P2)}
⇒ {uiff(Q1;Q2)}
⇒ {P1 + Q1
⇐⇒ P2 + Q2})
Proof
Definitions occuring in Statement :
uiff: uiff(P;Q)
,
uall: ∀[x:A]. B[x]
,
prop: ℙ
,
guard: {T}
,
iff: P
⇐⇒ Q
,
implies: P
⇒ Q
,
union: left + right
Definitions unfolded in proof :
guard: {T}
,
or: P ∨ Q
,
uall: ∀[x:A]. B[x]
,
implies: P
⇒ Q
,
uiff: uiff(P;Q)
,
and: P ∧ Q
,
iff: P
⇐⇒ Q
,
uimplies: b supposing a
,
member: t ∈ T
,
prop: ℙ
,
rev_implies: P
⇐ Q
Lemmas referenced :
or_wf,
uiff_wf
Rules used in proof :
sqequalSubstitution,
sqequalRule,
sqequalReflexivity,
sqequalTransitivity,
computationStep,
Error :isect_memberFormation_alt,
lambdaFormation,
sqequalHypSubstitution,
productElimination,
thin,
independent_pairFormation,
unionElimination,
inlFormation,
independent_isectElimination,
hypothesis,
hypothesisEquality,
inrFormation,
cut,
introduction,
extract_by_obid,
isectElimination,
Error :inhabitedIsType,
Error :universeIsType,
universeEquality
Latex:
\mforall{}[P1,P2,Q1,Q2:\mBbbP{}]. (\{uiff(P1;P2)\} {}\mRightarrow{} \{uiff(Q1;Q2)\} {}\mRightarrow{} \{P1 + Q1 \mLeftarrow{}{}\mRightarrow{} P2 + Q2\})
Date html generated:
2019_06_20-AM-11_17_22
Last ObjectModification:
2018_09_26-AM-10_24_50
Theory : core_2
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